Field of the Invention
The present invention relates to a liquid discharge head that discharges a liquid such as ink, and to a liquid discharge apparatus that includes such the liquid discharge head.
Description of the Related Art
In recent years, liquid discharge apparatuses are being used as printers for high-speed commercial printing as well as for business uses. When using the liquid discharge apparatuses for such purposes, a line head (a page-wide type liquid discharge head) in which recording element substrates are arrayed across the entire width of a recording medium is used to increase the printing speed. A recording element substrate is mainly manufactured from a silicon wafer or the like, and a substrate whose length is between approximately 10 mm to 40 mm is used in consideration of the yield and the like. Therefore, to construct a line head, it is necessary to arrange a plurality of recording element substrates in the width direction of the recording medium. A staggered arrangement system (Japanese Patent Application Laid-Open No. 2016-000489) and an inline arrangement system (Japanese Patent Application Laid-Open No. 2015-174385) are known as systems for arranging recording element substrates. In the staggered arrangement system, adjacent recording element substrates are arranged in an alternately staggered manner in a conveyance direction of the recording medium. In the inline arrangement system, adjacent recording element substrates are arranged in a straight line.
It is widely known that in order to prevent liquid inside a liquid discharge head from vaporizing and then thickening and coagulating in a liquid discharge apparatus when ink is not being discharged, it is effective to cover the discharge ports with a cap member. The vapor pressure around the discharge ports can be maintained in a saturated state by the cap member, and the amount of evaporation of liquid from the discharge ports when ink is not being discharged can be reduced.
In Japanese Patent Application Laid-Open No. 2015-174385, it is disclosed that a cover member (stationary plate) provided on a face that is opposed to a recording medium of a liquid discharge head has an opening that exposes discharge ports. When a cap member is brought into contact with the cover member, the flatness of the contacting portion can be maintained and the airtightness can be increased. The cover member includes a beam that extends between recording element substrates.
When separating the cap member from the cover member after the cap member has been brought into contact with the cover member, the cover member receives a force from the cap member which is a force in a direction that will cause the cover member to peel off from the liquid discharge head. To withstand this force, it is desirable for the cover member to be difficult to deform, that is, for the cover member to have a high degree of rigidity. The shape of the opening in the cover member differs between a staggered arrangement system and an inline arrangement system, and although a difference exists between the respective rigidities that is attributable to the difference between the shapes of the opening, it is desirable for the cover member to have a high degree of rigidity in each of these kinds of arrangement systems. Although the beam described in Japanese Patent Application Laid-Open No. 2015-174385 has an effect of increasing the rigidity of the cover member, there is a possibility that the beam will widen a space between recording element substrates and result in an increase in the size of the liquid discharge head.